Any suggestions on how to improve the code shown below for the Go-tour exercise?
Exercise description:
There can be many different binary trees with the same sequence of values stored at the leaves. A function to check whether two binary trees store the same sequence is quite complex in most languages. We'll use Go's concurrency and channels to write a simple solution.
This example uses the tree package, which defines the type:
type Tree struct { Left *Tree Value int Right *Tree }
Implement the
Walk
function.Test the
Walk
function.The function
tree.New(k)
constructs a randomly-structured binary tree holding the values k, 2k, 3k, ..., 10k.Create a new channel ch and kick off the walker:
go
Walk(tree.New(1), ch)
Then read and print 10 values from the channel. It should be the numbers 1, 2, 3, ..., 10.Implement the
Same
function usingWalk
to determine whethert1
andt2
store the same values.Test the Same function.
Same(tree.New(1), tree.New(1))
should return true, andSame(tree.New(1), tree.New(2))
should return false.Code skeleton:
package main import "golang.org/x/tour/tree" // Walk walks the tree t sending all values // from the tree to the channel ch. func Walk(t *tree.Tree, ch chan int) // Same determines whether the trees // t1 and t2 contain the same values. func Same(t1, t2 *tree.Tree) bool func main() { }
Solution:
package main
import (
"code.google.com/p/go-tour/tree"
"fmt"
)
// Walk walks the tree t sending all values
// from the tree to the channel ch.
func Walk(t *tree.Tree, ch chan int) {
if t.Left != nil {
Walk(t.Left, ch)
}
ch <- t.Value
if t.Right != nil {
Walk(t.Right, ch)
}
}
// Same determines whether the trees
// t1 and t2 contain the same values.
func Same(t1, t2 *tree.Tree) bool {
c1 := make(chan int, 10)
c2 := make(chan int, 10)
go Walk(t1, c1)
go Walk(t2, c2)
for i := 0; i < 10; i++ {
x, y := <-c1, <-c2
fmt.Printf("x: %v, y: %v\n", x, y)
if x != y {
return false
}
}
return true
}
func main() {
fmt.Println(Same(tree.New(1), tree.New(1)))
fmt.Println(Same(tree.New(1), tree.New(2)))
}